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81.
Jasmonates are signalling molecules induced in plants as a response to various biotic and/or abiotic stresses. As ozone is known to activate defense responses in plants, we have monitored the concentration of jasmonic acid in tomato leaves during and after an acute exposure to this abiotic elicitor. In this experiment, we observed that the maximum induction of jasmonic acid in O3-fumigated plants occurred 9 h after the end of treatment and the concentration of jasmonic acid in stressed plants increased 13-fold. However, the level of endogenous methyl-jasmonate was constant during the observed period. The extraction and quantification of jasmonic acid as its methyl ester was performed by headspace-solid-phase microextraction (or HS-SPME) in combination with GC-FID and GC-MS. The sensitivity (LOD = 2 ng/g) of this method permitted the detection and quantification of jasmonic acid present in plant tissues at very low concentrations. 相似文献
82.
García-Fernández RA Pérez-Martínez C Alvarez JE Navarrete AJ García-Iglesias MJ 《Veterinary dermatology》2006,17(1):36-44
Epidermal morphogenesis was studied in vivo following prenatal exposure to retinoic acid (RA). In pregnant mice, a single oral dose of RA on day 11.5 of gestation failed to induce histological changes in fetal epidermal development except in epidermal thickness. Epidermal thickness increased from 16.5 days post-coitum (dpc) onwards, and temporal and spatial epidermal modifications in keratins K5 and K14 related to proliferative activity of keratinocytes were observed. An RA effect on cell proliferation was supported by a statistically significant increase in the number of epidermal S-phase cells, containing BrdU-incorporated DNA in RA-exposed mice compared with nonexposed animals. The prolonged in utero action of RA on epidermal proliferative activity in fetuses and newborns suggests a long-term RA effect that may play a role on the development and evolution of diseases in adult skin. 相似文献
83.
Berkefeld H Sailer CA Bildl W Rohde V Thumfart JO Eble S Klugbauer N Reisinger E Bischofberger J Oliver D Knaus HG Schulte U Fakler B 《Science (New York, N.Y.)》2006,314(5799):615-620
Large-conductance calcium- and voltage-activated potassium channels (BKCa) are dually activated by membrane depolarization and elevation of cytosolic calcium ions (Ca2+). Under normal cellular conditions, BKCa channel activation requires Ca2+ concentrations that typically occur in close proximity to Ca2+ sources. We show that BKCa channels affinity-purified from rat brain are assembled into macromolecular complexes with the voltage-gated calcium channels Cav1.2 (L-type), Cav2.1 (P/Q-type), and Cav2.2 (N-type). Heterologously expressed BKCa-Cav complexes reconstitute a functional "Ca2+ nanodomain" where Ca2+ influx through the Cav channel activates BKCa in the physiological voltage range with submillisecond kinetics. Complex formation with distinct Cav channels enables BKCa-mediated membrane hyperpolarization that controls neuronal firing pattern and release of hormones and transmitters in the central nervous system. 相似文献
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Schroeder C Horner S Bürger N Engemann C Bange U Knoop EV Gabert J 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(7-8):290-296
The low sensitivity of the IBR-gE ELISA compared to other diagnostic ELISA tests for IBR is a major disadvantage of IBR control programmes based on IBR marker vaccination. Therefore the IBR-gE ELISA is not generally recommended for testing pooled or bulk milk samples.The aim of this study was to determine the performance of a commercially available kit for concentrating and purifying antibodies in milk in order to improve the sensitivity of detecting IBR-gE antibody positive cows from pooled and bulk milk samples. A single IBR-gE positive cow is likely to remain undetected in a pool of 49 negative milk samples without concentration. By contrast, the bulk milk concentration procedure improved sensitivity from 5.4% to 75.7% in a positive herd. Milk samples with a high or moderate positive signal are more likely to be detected after pool milk concentration compared to weak positive samples. Whereas a follow up study involving a monthly testing of bulk milk samples from three marker vaccinated IBR-gE negative herds over a period of seven months yielded negative results each month, bulk milk from a herd containing <5% IBR-gE positive cows always detected positive after concentration. Although the milk concentration procedure had no impact on specificity, it significantly enhanced the sensitivity of the detection of IBR-gE positive milk in pooled and bulk milk samples. After further evaluation this procedure could allow a cost efficient and reliable method of monitoring IBR marker-vaccinated herds for IBR-gE antibodies. 相似文献
88.
In the mixed crop-livestock farming system of Ethiopia where crop residues are the major feed resources and concentrate supplement feeds are not common, home-grown legume protein sources can help to minimise the feed problem. A 69-day feeding experiment on sheep was conducted to evaluate the potential of sweet blue lupin (Lupinus angustifolius L.) cultivar Sanabor seed as a substitute for commercial concentrate supplement. Thirty yearling male intact Washera sheep with initial body weight of 21 ± 1.38 kg (mean ± SD) were used. The design was a randomised complete block design with six replications. The five experimental supplement feeds were 453 g concentrate (T1), 342 g concentrate + 74 g lupin seed (T2), 228 g concentrate + 147 g lupin seed (T3), 116 g concentrate + 219 g lupin seed (T4) and 290 g lupin seed (T5) in dry matter basis to supplement around 100 g crude protein per day per animal. There were significant differences (P < 0.05) in total dry matter, crude protein, ash and organic matter intakes among treatments. The average daily body weight gain for T1, T2, T3, T4 and T5 was 91, 79, 79, 87 and 74 g/day, respectively, and this difference was not significant (P > 0.05). It was concluded that blue lupin seed has a potential to substitute the commercial concentrate supplement feed in Ethiopia. 相似文献
89.
Favrot C Steffan J Seewald W Hobi S Linek M Marignac G Olivry T Beco L Nett C Fontaine J Roosje P Bergvall K Belova S Koebrich S Pin D Kovalik M Meury S Wilhelm S 《Veterinary dermatology》2012,23(1):45-50, e11
Hypersensitivity dermatitides (HD) are commonly seen in cats, and they are usually caused by environmental, food and/or flea allergens. Affected cats normally present with one of the following clinical reaction patterns: head and neck excoriations, usually symmetrical self-induced alopecia, eosinophilic skin lesions or miliary dermatitis. Importantly, none of these clinical presentations is considered to be pathognomonic for HD skin diseases, and the diagnosis of HD is usually based on the exclusion of other pruritic diseases and on a positive response to therapy. The objectives of this study were to propose sets of criteria for the diagnosis of nonflea-induced HD (NFHD). We recruited 501 cats with pruritus and skin lesions and compared clinical parameters between cats with NFHD (encompassing those with nonflea, nonfood HD and those with food HD), flea HD and other pruritic conditions. Using simulated annealing techniques, we established two sets of proposed criteria for the following two different clinical situations: (i) the diagnosis of NFHD in a population of pruritic cats; and (ii) the diagnosis of NFHD after exclusion of cats with flea HD. These criteria sets were associated with good sensitivity and specificity and may be useful for homogeneity of enrolment in clinical trials and to evaluate the probability of diagnosis of NFHD in clinical practice. Finally, these criteria were not useful to differentiate cats with NFHD from those with food HD. 相似文献
90.
Domenico Robbe Augusto Carluccio Alessia Gloria Alberto Contri Mario Ventura Claudia Rita Catacchio Paola Straticò Lucio Petrizzi 《Journal of Equine Veterinary Science》2012
A 4-day-old male Martina Franca donkey foal was evaluated for a forelimb alteration. Clinical examination and radiographs revealed the agenesia of the distal digit. Biochemical parameters were normal, and ultrasonographic evaluation did not identify any relievable organ alteration. Karyotype study revealed an abnormality on chromosome 1. The foal was discharged with a distal limb bandage in which a palmar splint was applied. A poor prognosis for the functionality of the limb was given. In endangered species, such as the Martina Franca donkey, the excessive inbreeding could result in an increase in genetic disorders. These findings shed new light on the possible pathogenesis of the digital dysgenesia. The study of the karyotype could be a useful approach to detect genetic alterations that could or could not be expressed in the animal, especially in endangered species in which a risk of an excessive inbreeding is considerable. These defects should be considered in the choice and selection of the breeders. 相似文献